Deep-well pumps



y o. KRIEGBAUM 2,710,579

DEEP-WELL PUMPS 2 sheets-sheet 1 In ven/or:

arr KmEGB/wn ...1. u w A w W W n Sv l! J.. I. f @A mw f lnLln// f 7Jr/7///Ar/// United States This invention relates to means for raisingliquid from deep wells, bore holes, shafts and the like, hereinaftergenerally referred to as bore holes, more particularly from those ofgreat depth.

It is known to pump water, oil or the like out of bore holes by means ofa centrifugal pump arranged upon the bottom of the bore hole andconnected by means of a long shaft with a motor at the surface. Suchdevices are unsatisfactory, because they involve, especially in the caseof deep bore holes, great expenditure of constructional materials, andin consequence of the friction in numerous bearings they dissipate agreat deal of power.

On account of these defects, so-called sub-aqueous or submerged pumpshave been adapted instead. Here it is a question of an electric motorevolved for this purpose, which is combined with the pump, and can besuspended in the bore hole with the latter as a structural unit. Withthese composite units the electric motors have to be provided with adiving bell, to protect the winding from the water. Otherwise the motorswould have to be constructed as submerged rotors, the rubberinsulatedwinding of which can remain in the water. It is however that the motorsof submerged pumps, notwithstanding all precautions, are very -sensitiveand notsufciently reliable in operation. Upon failure of the diving-belldevice, or in the case of the smallest leakage of the submerged rotorwinding or of the current-supply cables, the entire unit becomesinoperative. If these pumping units are employed for raising oil, thereis a further disadvantage in the risk that in the event of sparking, andthe occurrence of oil gases, explosions may occur. I t is particularlydisadvantageous, however, that the motors of submerged pumps, with theusual number of 50 periods per second, only permit of a speed of notmore than 3000 revolutions per minute. At this speed, however, asinglestage centrifugal pump of moderate power attains a delivery heightof only about 50 to 60 metres. For bores of greater depth, therefore,multi-stage submerged pumps are necessary. These however involve morepowerful driving motors, which in their turn, on account of their largerdimensions, pre-suppose bore holes of larger diameter. The greater thediameter of the bore hole, however, the more does. the expenditure oftime, labour, material and money for sinking the bore hole increase.Known subaqueous or immersion pumps of an eiciency which is satisfactoryas regards both power and price are therefore available only for limitedbore-hole depths.

It would be possible to install above ground a relatively large ordinarycentrifugal pump the pressure water of which would be supplied for thegreater part to a water-jet pump located in the bore hole, and theservice water of which, together with its power water, would be suppliedto the centrifugal pump at the ground level. Water-jet pumps, however,as is known, have a very low efhciency, and are therefore likewiseinadmissible, apart from the question of dimensions, for the raising ofliquid from bore holes.

According to the invention the problem set forth is arent I lil solvedin a simple and advantageous manner by associating with apressure-medium generator, for instance a rain pump, located at thesurface level, an engine set capable of being inserted in the bore hole,consisting of a rotary engine operated by the pressure fluid, forinstance a turbine, and a centrifugal pump or turbine pump driventhereby. Preferably the construction is such that the turbine and thecentrifugal pump form a unit, that is to say, they can be put in andbrought out as a unitary structural whole. Preferably the turbine rotorand the pump impeller will be mounted upon a common shaft.

The turbine is fed by the main pump. It sets in rotation, thecentrifugal pump, which sucks out of the borehole the liquid to beraised, water for example, and feeds it through a delivery pipe,together with the operative liquid of the turbine, water for instance,to the main pump at the surface. This pump diverts the service water tothe consumer and returns the power water to the turbine in the borehole.

For the path of the water through the machine unit there are twopossibilities. The arrangement may be such that the turbine consumeseither the entire head right down to the pressure before admission tothe centrifugal pump, or it may be such that the turbine consumes onlythe head down to the delivery pressure of the centrifugal pump. in theformer case the water that drives the turbine is either discharged fromthe turbine into the ground water at the bottom or is fed directly tothe suction side of the centrifugal pump, and from the latter isconveyed, together with the service water, to the main pump. In thesecond case the power water consumed by the turbine, together with thewater delivered by the centrifugal pump, is fed directly to the mainpump. The second solution is to be preferred, on the ground of betterover-all efficiency.

Since for the functioning of the engine set consisting of the turbineand the centrifugal pump the relieving of the axial thnlst of turbineand pump is important, a further feature of the invention consists in soarranging the pump rotor and the turbine rotor that their axial thrustsare opposite to one another, and thereby to a material extent counteractone another. This opposite arrangement of the turbine and pump rotors isobtained by arranging the turbine and pump in such a way that the waterflows in to both from above, or to both from below.

A further possibility for relieving axial thrusts consists in the use ofa balancing or relieving disc known in itself, which here however, in afurther development of the inventions, serves for relieving the entirerotor embracing the pump impeller and the turbine wheel, and is soarranged that it is subjected on one side to the highest pressureoccurring, namely the pressure before the turbine inlet, and on theother side to the lowest pressure, namely the pressure before the pumpinlet. This renders it possible, with a comparatively small balancingdisc, to obtain an extensive balancing of the axial thrusts.

To the balancing disc, according to a further feature of the invention,the pressure water is supplied with the pressure before the turbine,preferably through the common shaft, constructed as a hollow shaft. Itis advisable in this case to pass the pressure water through the lowerguide bearing of the shaft for the lubrication thereof. On this accountthe balancing disc may be arranged between the centrifugal pump and thelower journal bearlng.

In a further development of the ideas of the invention with respect tobalancing, it is provided to bring about another special partialbalancing of the axial thrust of the turbine by equipping the disc whichcarries the blading of the turbine wheel, and which is provided both onthe admission side and on the exhaust side with a gap packing, withaxial ducts, which serve to equalize the pressure on both sides or" theturbine wheel. rihe construction may be such that the water flowingoutwards through the gaps passes through the upper journal bearing ofthe shaft for the lubrication thereof. This water passing through theclearance space is preferably withdrawn at the same place as thepressure water for the balancing disc. ln order to prevent sand enteringthe bearings and the clearance packings a lter may be interposed beforethe point of withdrawal of the balancing, clearance-paclting andlubricating water.

It is advisable to provide the turbine with a distributor or guideapparatus and a rotor of axial construction. The channels are then openon all sides. Consequently there is the advantage of simplicity ofmanufacture. A par ticularly important advantage is that thisconstruction enables the diameter of the casing to be kept small.

The pump may have a runner of radial or semiaxial constmction. ifdesired it may even have a channel rotor. it will preferably have aone-piece inlet and cutlct guide, the admission part of which may serveat the same time as a casing for the balancing water.

For the attainment of an upwardly directed axial thrust counteractingthe intrinsic weight of the rotor, it would be possible, if desired toadmit the water into the irnpeller of the pump from above. 1n this casethe impeller side plate may be employed as a rotating balancing disc,and the guide-wheel side plate as a stationary thrust disc orcounter-disc.

It has also been found particularly advantageous to provide the machineunit with two concentric tubes, to the inner one of which the pipe forthe power water for the turbine can be connected, and to the outer onethe pipe for the delivery water. The machine set therefore possesses, ina sense, a casing consisting of two concentric cylinders, which areequipped with pipe unions for the power-water and delivery-water pipesone inside the other. This construction helps to keep the over-alldiameter small so that a pumping unit of comparatively large power canbe introduced into narrow bore holes.

By this invention the defects hereinbefore described of known devicesare obviated. ln particular the liability to disturbance inherent inknown deep-wall pumps is eliminated. Since the main pump, at the groundlevel, may be driven not only by an electric motor but even by a heatengine, the pumping apparatus according to the invention is entirelyindependent of any source of current. Accordingly the main pump ischaracterised by an extensive adaptability to practical operation. Sinceany required pressure may be adopted for the pressure medium aboveground., the centrifugal pump may be driven at a speed corresponding tocurrent needs. An increase in speed, which is thus readily obtainable,leads however to a considerable increase in the lift or delivery head.With this is associated a further important advantage. Since thequantity delivered increases in proportion to the increase in speed, itis possible, without reducing the delivery, to employ a smaller pump andtherefore a narrower bore hole. This however is already of greatimportance, on account of the time and expense involved in sinking abore hole. When raising liquid from a group of deep wells there is thespecial advantage that the pressure uid can be provided by a single mainpump, feeding a number of machine sets located in different bore holes.rom this single main pump the service water raised from all the deepwells can then of course be led to the various consumer points. Sincethis involves a comparatively large main pump, the latter will work withvery good eiciency.

Further features and advantages of the invention are explained in theensuing description of the drawing, which illustrates a fewconstructional examples of the invention.

Figures l and 2 are diagrammatic views representing Lil) liti

75 portions of which are in one piece.

the fundamental arrangement according to the invention with Figure 2showing a modification of Figure l.

Figure 3 is a longitudinal section of a portion of a turbine pump foruse in the arrangement according to Figure 2.

Figure 4 is a longitudinal section showing a modification of Figure 3.

Figure 5 is a longitudinal section showing a further form ofconstruction.

A motor 1 drives a main pump 2, which is located at the surface level,and which supplies the water raised partly as service water to aconsumer, for instance to a reservoir 3, and partly as power water to aturbine 5 located in the bore hole 4. This turbine, together with acentrifugal pump 6 driven thereby, forms a machine unit which can beconveniently introduced into and withdrawn from a bore hole.

1n the construction illustrated in Figure 1, the water leaving theturbine 5 ilows on to the bottom of the bore hole and then directly intothe suction inlet of the pump 6, which furthermore draws in the servicewater by suction and forces it, together with the power water from theturbine 5, to the main pump 2.

In the construction according to Figure 2, the same pressure prevails atthe turbines outlet as on the pressure side of the bore hole pump 6, sothat the water leaving the turbine can be introduced directly into thedelivery pipe of this pump.

The turbine pump unit of Figure 3 comprises two concentric pipes 7 and8. The pipe 7 can be connected to the pipe through which power waterHows to the turbine. The pipe 8 is connected to the delivery pipe.

Upon a hollow shaft 9, which is supported by means of two guide orjournal bearings 10 and 11, is mounted the turbine blading 12 and thepump wheel 13. From the turbine the power water flows by way of a bend14 into the delivery pipe 8, while the service water, sucked in by thepump from the bottom of the bore hole through an annular space 15 passesthrough an annular space 16 into the delivery pipe S. In the latter theservice water, together with the power water, flows to the main pump 2.

Between the lower guide bearing 11 and the pump impeller 13 there ismounted upon the common hollow shaft 9, a counter disc 17, which on itsupper surface is subjected to the pressure that prevails on the suctionside of the pump. The pressure water for the other side or space 17 ofthe balancing disc is taken from the pipe 7 at a point 18 at the upperend of the hollow shaft 9 and is supplied through the hollow shaft 9 andaround its lower end to the counter disc 17. On its way the pressurewater ows through the lower guide bearing 11 and effects the lubricationthereof.

A filter 19 is preferably located in front of the withdrawal point 18 atthe upper end of the hollow shaft 9, so that sand and other foreignsubstances are excluded.

A turbine-pump unit of Figure 4 is distinguished from that of Figure 3primarily by the fact that an additional balancing device for theturbine wheel 12 is provided. This balancing device is sealed inrelation to the machine body on the inlet side and On the outlet side bymeans of clearance gap packings 2G and 21, and is furthermore providedwith ducts 22 which connect the two sides with one another, so as toequalise the pres- Part of the water flows through a duct 23 and thehollow shaft 9 to the counter disc 17 and passes through a bearing 24,which is lubricated and acts as a water seal for the clearance-gappacking on the admission side of the turbine, and in consequence of theducts 22 to the clearance-gap packing 21 on the exhaust side of theturbine.

In the constructional example of Figure 5, for the pump impeller, aninsertible distributor or guide apparatas 25 surrounding it is provided,the inlet and outlet The inlet portion of this guide apparatus serves atthe same time as a casing for the water of the counter disc 17.

As Figure 5 shows, the machine set may be suspended from a stationaryjacket tube 26, which is equipped with a carrying ring 27, upon whichthe casing of the turbine pump unit rests in a uidtight manner. Whensuch a jacket tube is used, the outer delivery tube 8 may be omitted,The jacket tube greatly facilitates the introduction and withdrawal ofthe machine set and of the associated suction pipe and the foot valvethat shuts olf the latter. In particular in the case of great depths thejacket tube presents noteworthy advantages. When installing the machineset the jacket tube is introduced first, after which the suspension ofthe machine set, with its power-water pipe, can be quickly and easilyeifected. When removing the machine set the jacket tube may remain inthe bore hole.

The pressure medium, that is, in the case of pumping water, the powerwater, need not necessarily be supplied to the turbine by a main pump.Any other suitable means of producing pressure uid may be employed. Thusfor example the power water pipe may be connected to a hydraulic main.

Having now particularly described and ascertained the nature of my saidinvention and in what manner the same is to be performed, I declare thatwhat I claim is:

1. Apparatus for raising liquids from deep wells, bore holes, shafts andthe like, more particularly from those of great depth and operable by apressure fluid, comprising a machine unit which is capable of beingintroduced into the well and having an axial turbine operated by thepressure uid and a centrifugal pump driven by and arranged below theturbine, a hollow shaft in the unit on which the turbine and pump aremounted for conveying a liquid drive medium, a pair of concentricallyarranged pipes one of which is connected to the centrifugal pump toconvey the liquid from the well and the other is connected to theturbine to receive the liquid from the shaft, a counter disc mounted onthe shaft between the pump and the bottom end of the shaft which on oneside is subjected to the pressure of the turbine inlet and on the otherside to the pressure of an inlet of the centrifugal pump, and a lowerguide bearing on the bottom end of the shaft.

2. Apparatus for raising liquids according to claim l in which gappackings connected by ducts are provided at the inlet and outlet ends ofthe turbine to equalize pressure.

3. Apparatus for raising liquids according to claim 1, in which a filteris provided at the top end of the hollow shaft.

References Cited inthe file of this patent UNITED STATES PATENTS1,609,306 Peterson Dec. 7, 1926 1,739,000 Jordao Dec. 10, 1929 1,818,455Bigelow Aug. 11, 1931 1,894,393 Bigelow Ian. 17, 1933 2,516,822 YatesJuly 25, 1950 FOREIGN PATENTS 148,466 Great Britain Dec. l2, 1921244,176 Great Britain Dec. 14, 1925 309,856 Germany Dec. 18, 1918380,867 Germany Sept. 13, 1923 466,729 France Mar. 11, 1914

1. APPARATUS FOR RAISING LIQUIDS FROM DEEP WELLS, BORE HOLES, SHAFTS ANDTHE LIKE, MORE PARTICULARLY FROM THOSE OF GREAT DEPTH AND OPERABLE BY APRESSURE FLUID, COMPRISING A MACHINE UNIT WHICH IS CAPABLE OF BEINGINTRODUCING INTO THE WELL AND HAVING AN AXIAL TURBINE OPERATED BY THEPRESSURE FLUID AND A CENTRIFUGAL PUMP DRIVEN BY THE ARRANGED BELOW THETURBINE, A HOLLOW SHAFT IN THE UNIT ON WHICH THE TURBINE AND PUMP AREMOUNTED FOR CONVEYING A LIQUID DRIVE MEDIUM, A PAIR OF CONCENTRICALLYARRANGED PIPES ONE OF WHICH IS CONNECTED TO THE CENTRIFUGAL PUMP TOCONVEY THE LIQUID FROM THE WELL AND THE OTHER IS CONNECTED TO THETURBINE TO RECEIVE THE LIQUID